Stair structure



Feb. 20, 1962 F. J. BLAIR 3,021;92s

STAIR STRUCTURE Filed May 22, 1957 INV'ENTOR.

3,921,928 SHAH STRUCTURE Francis 3. Blair, 4149 Minnetonira Drive, Loon Lake, Linden, Mich. Filed May 22, 1957, Ser. No. 660,868 2 (Claims. (Cl. 18943) This invention relates to an all metal stair structure in which the parts may be quickly and easily assembled.

The main objects of this invention are:

First, to provide a stair assembly comprising a plurality of duplicate step units formed as castings which may be quickly and easily assembled with supporting stringers and provided with hand rails and rail supporting struts.

Second, to provide a stair structure in which the step units may be economically produced as aluminum castings and at the same time are so formed as to be very strong.

Third, to provide a stair structure having these advantages in which the pa ts may be economically produced and very rapidly assembled in stairs with the desired number of steps.

Objects relating to details and economies of the invention will appear from the description to follow. The invention is defined and pointed out in the claims.

A preferred embodiment of the invention is illustrated in the accompanying drawing, in which:

FIG. 1 is a side elevational view of a stair structure or assembly embodying my invention, portions being broken away to show structural details and supporting upper and lower surfaces being conventionally illustrated.

FIG. 2 is an enlarged vertical section of one of the step units of a stair assembly on a line corresponding to line 22 of FIG. 4 in which figure only a single step unit is illustrated.

FIG. 3 is a perspective view of one of the step units.

FlG. 4 is a rear view of one of the step units.

FIGS. 5 and 6 are fragmentary sectional views on lines corresponding to section lines 55 and 6-6 respective ly or FIG. 1 showing details of the coupling of the hand rails to the spindles.

FIGS. 7 and 8 are fragmentary views partially in section on lines 7-7 and 8-8 respectively of FIG. 1 showing details of the coupling for the spindle, struts and spindles.

In the accompanying drawing 1 represents a lower surface and 2 an upper surface with which the stair assembly of my invention is associated.

The stair assembly of my invention comprises a plurality of step units designated generally by the numeral 3 formed as integral castings, desirably of aluminum. Thesestep units comprise the treads 4 and triangular end members 5, 5, the end members terminating at their lower edges on bead-like tubular enlargements 6.

At their forward edges the treads have downwardly projecting flanges 7 which merge into the inwardly projecting flanges 8 of the end members 5. At the rear edges the steps have upwardly turned flanges 9. The end members have spindle sockets 18 formed integrally therewith, the inner walls of the sockets 11 being boss-like projections on the inner sides of the end members. These also serve as bracing elements at the upper ends thereof merge into the tread.

These step units are sleeved upon the rod or bar-like stringers 12 in abutting relation as is shown in FIGS. 1 and 2 with the upturned flanges 9 of one unit fitting between the side members of the next upper unit.

In the embodiment illustrated the risers are embedded at their lower ends in the floor or base 1 and they are provided with thrust collars 18 with which the lower unit is in thrust supported engagement. At their upper 3,h2l,928 Patented Feb. 2%, 1%62 ends the stringers are provided with coupling members 14 supportedly mounted on the upper fioor or surface 2.

The spindles 15 are threaded into the sockets 10 and are provided with coupling members 16 having down- Wardly facing sockets engaging the upper ends of the spindles. These coupling members have aligned bores 1'7 through which the rails 18 are disposed and secured as by set screws or other suitable means not illustrated.

The coupling members 16 serve as finishing members for the upper ends of the spindles, see FIGS. 1, 5 and 6. Spindle strut or brace rods 19 are preferably provided, these being secured to the spindles by means of the coupling members 29 sleeved upon the spindles and secured thereto intermediate their length, the coupling members being provided with bores 21 through which the strut rods are disposed.

At their upper end the hand rails are provided with curved portions 22 desirably formed separately from the rails 18, and the extensions 23.

This structure and arrangement of parts results in a very attractive stair and one which is readily adapted to meet particular conditions and stairs varying in height.

t will be understood that the angle of the stairs is predetermined by the particular units but the units may be readily varied to meet particular requirements.

The step units are, as stated, desirably made of aluminum and the coupling members and hand rails and strut rails may also desirably be made of aluminum, particularly to harmonize in the matter of color and avoids the necessity of painting.

I have not attempted to illustrate such variations as it is believed that this disclosure will enable those skilled in the art to embody or adapt the invention as may be desired.

Having thus described the invention, what is' claimed to be new and is desired to secure by Letters Patent is:

1. A metal stair assembly comprising laterally spaced rod-like stringers, a plurality of step units, each step unit being integrally moulded and comprising a tread and depending triangular end members having outwardly projecting continuous tubular bead-like enlargements on their lower edges sleeved upon said stringers with their ends in thrust abutting engagement, said steps having upturned flanges on the rear edges thereof disposed between and in end and in lateral thrust supporting engagement with the inner sides of the end members of the adjacent upper step unit.

2. A stair assembly comprising laterally spaced rod like stringers, a plurality of integral step units, each step unit comprising a tread and depending triangular end members having continuous tubular enlargements on their lower edges sleeved upon said strin ers with their ends in thrust sustaining abutting engagement, the ends of the treads overlapping said end members and being free from drainage obstruction, said steps having upwardly and rearwardly projecting flanges on their rear edges disposed between and in lateral thrust supporting engagement with the inner sides of the end members of the adjacent upper step unit, said flanges acting to align and sustain lateral thrust of said step units relative to each other.

References Qited in the file of this patent UNITED STATES PATENTS 290,878 Haas Dec. 25, 1883 340,263 Weber Apr. 20, 1886 705,794 Snider July 29, 1902 1,547,254 McClure July 28, 1925 2,292,046 Burton Aug. 4, 1942 2,471,352 Safir May 24, 1949 2,767,959 Schott Oct. 23, 1956 

